Wireless rogowski coil system

Patent metadata

Field	Value
Publication number	US-10473696-B2
Application number	US-201715470420-A
Country	US
Kind code	B2
Filing date	Mar 27, 2017
Priority date	Sep 25, 2014
Publication date	Nov 12, 2019
Grant date	Nov 12, 2019

Abstract

A Rogowski coil in a sensor unit has voltage induced by a conductor surrounded by the Rogowski coil. The voltage is integrated to represent current which is converted to digital data representing current in the conductor and sent wirelessly to a multimeter. The sensor unit may receive control signals from the multimeter and a remote control apparatus. A plurality of sensor units may be networked and controlled by the remote control apparatus.

First claim

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. A method for measuring current in a conductor, the method comprising:
producing a first signal representative of current flow in a first electrical conductor, wherein the first signal is produced by a multimeter having a wireless transceiver, the multimeter being positioned with respect to the first electrical conductor to produce the first signal representative of current flow in the first electrical conductor;
wirelessly transmitting information corresponding to the first signal from the wireless transceiver of the multimeter;
producing a second signal representative of current flow in a second electrical conductor, wherein the second signal is produced by a Rogowski coil sensor unit separate from the multimeter, and wherein the Rogowski coil sensor unit includes a Rogowski coil positioned around the second electrical conductor; and
wirelessly transmitting information corresponding to the second signal from a wireless control unit operatively coupled to the Rogowski coil sensor unit,
wherein the information corresponding to the second signal is transmitted from the wireless control unit to the wireless transceiver of the multimeter and to a remote control apparatus that is separate from the multimeter and the Rogowski coil sensor unit, and
wherein the remote control apparatus is operable to directly communicate with the multimeter and the Rogowski coil sensor unit via wireless communication to receive the information corresponding to the first signal produced by the multimeter and the second signal produced by the Rogowski coil sensor unit and to send control signals to the multimeter and to the Rogowski coil sensor unit.

2. The method of claim 1 , further comprising integrating an electrical signal induced in the Rogowski coil to produce the second signal representative of the current flow in the second electrical conductor.

3. The method of claim 1 , wherein the multimeter further has a pair of clamp portions, the method further comprising positioning the clamp portions around the first electrical conductor.

4. The method of claim 1 , further comprising operating the Rogowski coil sensor unit in an idle mode in response to a control signal received from the remote control apparatus.

5. The method of claim 1 , wherein the information corresponding to the second signal is transmitted by the wireless control unit in response to a control signal received from the remote control apparatus.

6. The method of claim 1 , wherein the information corresponding to the second signal is automatically periodically transmitted from the wireless control unit.

7. The method of claim 1 , wherein the wireless control unit is coupled to the Rogowski coil sensor unit by a connecting cable and receives the second signal representative of current flow in the second electrical conductor.

8. A system for measuring current in a conductor, the system comprising:
a multimeter positionable with respect to a first electrical conductor to produce a first signal representative of current flow in the first electrical conductor, wherein the multimeter includes a wireless transceiver that is operable to wirelessly transmit information corresponding to the first signal;
a Rogowski coil sensor unit separate from the multimeter, wherein the Rogowski coil sensor unit includes a Rogowski coil that is positionable around a second electrical conductor to produce a second signal representative of current flow in the second electrical conductor, and a wireless control unit that is operatively coupled to the Rogowski coil sensor unit to wirelessly transmit information corresponding to the second signal; and
a remote control apparatus that is separate from the multimeter and the Rogowski coil sensor unit,
wherein the wireless control unit of the Rogowski coil sensor unit is adapted to wirelessly transmit the information corresponding to the second signal to the wireless transceiver of the multimeter and to the remote control apparatus, and
wherein the remote control apparatus is operable to directly communicate with the multimeter and the Rogowski coil sensor unit via wireless communication to receive the information corresponding to the first signal produced by the multimeter and the second signal produced by the Rogowski coil sensor unit and to send control signals to the multimeter and to the Rogowski coil sensor unit.

9. The system of claim 8 , wherein the Rogowski coil sensor unit further includes an integrator that integrates an electrical signal induced in the Rogowski coil to produce the second signal representative of the current flow in the second electrical conductor.

10. The system of claim 8 , wherein the multimeter further includes a pair of clamp portions that are positionable around the first electrical conductor.

11. The system of claim 8 , wherein the Rogowski coil sensor unit is operable in an idle mode in response to a control signal received from the remote control apparatus.

12. The system of claim 8 , wherein the wireless control unit is adapted to transmit the information corresponding to the second signal in response to a control signal received from the remote control apparatus.

13. The system of claim 8 , wherein the wireless control unit is adapted to automatically periodically transmit the information corresponding to the second signal.

14. The system of claim 8 , wherein the wireless control unit is coupled to the Rogowski coil sensor unit by a connecting cable and, in operation, receives the second signal representative of current flow in the second electrical conductor.

15. The system of claim 8 , further comprising a plurality of Rogowski coil sensor units separate from the multimeter and the remote control apparatus, wherein the Rogowski coil sensor units are each positionable around an electrical conductor to produce a signal representative of current flow in the respective electrical conductor, and wherein the Rogowski coil sensor units are each operatively coupled to a wireless control unit adapted to wirelessly transmit information corresponding to the produced signal representative of current flow in the respective electrical conductor.

Assignees

• Fluke Corp

Inventors

• Bannister Matthew Carl-Robert
• Epperson David Lawrence
• Huber Clark N

Classifications

• G01R15/125

  for digital multimeters · CPC title

• G01R15/181 Primary

  using coils without a magnetic core, e.g. Rogowski coils · CPC title

• G01R31/3025

  Wireless interface with the DUT · CPC title

• G01R15/12

  Circuits for multi-testers {, i.e. multimeters}, e.g. for measuring voltage, current, or impedance at will · CPC title

• G01R19/0092

  Measuring current only · CPC title